Denervation of the lateral humeral epicondyle for treatment of chronic lateral epicondylitis.

PURPOSE: Chronic lateral epicondylitis remains a treatment challenge. Traditional surgical treatments for lateral epicondylitis involve variations of the classic Nirschl lateral release. Anatomic studies reveal that the posterior branch or branches of the posterior cutaneous nerve of the forearm consistently innervate the lateral humeral epicondyle. We undertook the present study to determine the effectiveness of denervation of the lateral humeral epicondyle in treating chronic lateral epicondylitis. METHODS: An institutional review board-approved prospective study included 30 elbows in 26 patients. Inclusion criteria included failure to respond to nonoperative treatment for more than 6 months and improvement in grip strength and in visual analog pain scale after diagnostic nerve block of the posterior branches of the posterior cutaneous nerve of the forearm proximal to the lateral humeral epicondyle. We excluded patients who had undergone previous surgery for lateral epicondylitis. Outcome measures included visual analog pain scale and grip strength testing. Denervation surgery involved identification and transection of the posterior cutaneous nerve of the forearm branches with implantation into the triceps. The presence of radial tunnel syndrome was noted but did not affect inclusion criteria; if it was present, we did not correct it surgically. We used no postoperative splinting and permitted immediate return to activities of daily living. RESULTS: At a mean of 28 months of follow-up, the average visual analog scale score decreased from 7.9 to 1.9. Average grip strength with the elbow extended improved from 13 to 24 kg. A total of 80% of patients had good or excellent results, as defined by an improvement of 5 or more points on the visual analog scale for pain. CONCLUSIONS: Denervation of the lateral epicondyle was effective in relieving pain in 80% of patients with chronic lateral epicondylitis who had a positive response to a local anesthetic block of the posterior branches of the posterior cutaneous nerve of the forearm. Radial nerve compression syndromes must be evaluated as a confounding source of symptoms and may require additional treatment in patients who fail to improve with denervation alone. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Multielectron redox activity facilitated by metal-metal interactions in early/late heterobimetallics: Co/Zr complexes supported by phosphinoamide ligands.

To assess the effect of dative M-->M interactions on redox properties in early/late heterobimetallic complexes, a series of Co/Zr complexes supported by phosphinoamide ligands have been synthesized and characterized. Treatment of the Zr metalloligands (Ph(2)PN(i)Pr)(3)ZrCl (1), ((i)Pr(2)PNMes)(3)ZrCl (2), and ((i)Pr(2)PN(i)Pr)(3)ZrCl (3) with CoI(2) leads to reduction from Co(II) to Co(I) and isolation of the heterobimetallic complexes ICo(Ph(2)PN(i)Pr)(3)ZrCl (4), ICo((i)Pr(2)PNMes)(3)ZrCl (5), and ICo((i)Pr(2)PN(i)Pr)(3)ZrCl (6), respectively. Interestingly, treatment of CoI(2) with the phosphinoamine Ph(2)PNH(i)Pr in the absence of a bound Zr center leads to the disubstituted Co(II) complex (Ph(2)PNH(i)Pr)(2)CoI(2) (7). The tris(phosphinoamine) Co(I) complex (Ph(2)PNH(i)Pr)(3)CoI (8) can only be generated in the presence of an added reductant such as Zn(0), indicating that the reduction of Co(II) to Co(I) only occurs in the presence of Zr in the formation of complexes 4-6. Structural characterization of 4-6 reveals a Zr-Co interaction, with interatomic distances of 2.7315(5) A, 2.6280(5) A, and 2.6309(5) A, respectively. This distance appears to decrease as the phosphine donors on Co become more electron-releasing, strengthening the dative Co-->Zr interaction. Cyclic voltammetry of 4-6 shows that all three compounds can be further reduced by two electrons at relatively mild reduction potentials (-1.65 V to -2.07 V vs Fc/Fc(+)). The potentials at which these reductions occur in each of these complexes are largely governed by the extent to which electron-density is donated to Zr, as well as the electron-donating ability of the phosphine substituents. Moreover, cyclic voltammetry of complex 8 reveals that in the absence of Zr, the Co center is significantly more electron rich, and thus more difficult to reduce. Chemical reduction of 5 leads to the isolation of the two-electron reduced dinitrogen complex [N(2)Co((i)Pr(2)PNMes)(3)ZrX][Na(THF)(5)] (9). X-ray crystallography of 9 reveals that two-electron reduction is accompanied by a significant contraction of the Co-Zr interatomic distance from 2.6280(5) A to 2.4112(3) A. These heterobimetallic complexes have been studied computationally using density functional theory to examine the nature of the metal-metal interactions in these species.

Endoscopic resection of an intraventricular dysembryoplastic neuroepithelial tumor of the septum pellucidum.

Tumors located in the region of the foramen of Monro often present with signs and symptoms of obstructive hydrocephalus. Various types of lesions occur in this location. We describe a case of a dysembryoplastic neuroepithelial tumor of the septum pellucidum presenting with obstructive hydrocephalus and its successful endoscopic excision. The surgical considerations and pathologic findings are discussed.

A clinical approach to diagnosing wrist pain.

A detailed history alone may lead to a specific diagnosis in approximately 70 percent of patients who have wrist pain. Patients who present with spontaneous onset of wrist pain, who have a vague or distant history of trauma, or whose activities consist of repetitive loading could be suffering from a carpal bone nonunion or from avascular necrosis. The hand and wrist can be palpated to localize tenderness to a specific anatomic structure. Special tests can help support specific diagnoses (e.g., Finkelstein's test, the grind test, the lunotriquetral shear test, McMurray's test, the supination lift test, Watson's test). When radiography is indicated, the posterior-anterior and lateral views are essential to evaluate the bony architecture and alignment, the width and symmetry of the joint spaces, and the soft tissues. When the diagnosis remains unclear, or when the clinical course does not improve with conservative measures, further imaging modalities are indicated, including ultrasonography, technetium bone scan, computed tomography, and magnetic resonance imaging. If all studies are negative and clinically significant wrist pain continues, the patient may need to be referred to a specialist for further evaluation, which may include cineroentgenography, diagnostic arthrography, or arthroscopy.

Use of stereotactic intensity-modulated radiotherapy in thyroid-related ophthalmopathy. Case report.

Thyroid-related ophthalmopathy (TRO), a debilitating condition involving a range of visual and orbital symptoms, occurs in up to 40% of patients with Graves disease. The goals of treatment include correcting thyroid dysfunction, relieving ocular pain, preserving vision, and improving cosmetic appearance. Options for therapy include symptomatic treatment, glucocorticoid medication, radiation therapy, and surgery. Traditional radiation treatment uses small opposed bilateral fields consisting of retrobulbar volumes and customized blocks to shield periorbital structures. The combination of intensity-modulated radiotherapy (IMRT) and stereotactic technology facilitates the administration of radiation to patients suffering from TRO and provides greater safety and efficacy than traditional treatment. The authors present the case of a patient with severe TRO whose symptoms resolved rapidly after treatment with stereotactic IMRT. The outcome in this case supports stereotactic IMRT as an effective treatment option for patients with TRO who also undergo radiation therapy.

Abusive head injury as a cause of apparent life-threatening events in infancy.

BACKGROUND: An apparent life-threatening event (ALTE) refers to the sudden occurrence of a breathing abnormality, color change, or alteration in muscle tone or mental status in an infant. Several patients with ALTEs admitted to our institution were found to have sustained abusive head injuries. OBJECTIVE: To systematically examine the possible causes of ALTEs and their relative frequencies. STUDY DESIGN: Prospective consecutive case series of 243 infants younger than 12 months admitted to a tertiary care academic medical center for evaluation of an ALTE during a 32-month interval. RESULTS: Thirty-five different causes of ALTEs were identified. Six subjects (2.5%) were diagnosed as having abusive head injuries, or 1 admission every 5 months. Three patients died in the hospital, 2 of whom were diagnosed as having abusive head injuries. CONCLUSIONS: A wide spectrum of diseases and disorders can precipitate an ALTE. Among them, abusive head injury, a recently recognized cause, occurs frequently enough to obligate its inclusion in the differential diagnosis. An ophthalmologic evaluation with dilated fundus examination and cranial imaging should therefore be considered early in the investigation unless another cause becomes apparent soon after admission.

Update on treatment modalities for optic nerve sheath meningiomas.

Optic nerve sheath meningiomas (ONSMs) represent 1 to 2% of all meningiomas and one third of all optic nerve tumors. The management of ONSMs is controversial. Traditional surgical removal often results in postoperative blindness in the affected eye and thus has been abandoned as a treatment option in most patients. Surgery may be unnecessarily aggressive, especially if the patient has useful vision. When these tumors are left untreated, however, ensuing progressive visual impairment may lead to complete blindness. More recently, radiotherapy has gained wider acceptance as a treatment for these lesions. The authors of some reports have suggested that fractionated stereotactic radiosurgery (SRS) may be the best option for treating primary ONSMs. In patients with documented progressive visual deterioration, fractionated SRS may be effective in improving or stabilizing remaining functional vision. The authors review the clinical presentation, radiographic characteristics, and management of ONSMs, emphasizing the use of fractionated SRS.

Optic nerve sheath meningiomas: visual improvement after stereotactic radiotherapy.

OBJECTIVE: The management of primary optic nerve sheath meningioma (ONSM) is controversial. Surgery often results in postoperative blindness in the affected eye and thus has been abandoned as a treatment option for most patients. When these tumors are left untreated, however, progressive visual impairment ensues, which also leads to blindness. Recently, radiation therapy has gained wider acceptance in the treatment of these lesions. Experience with stereotactic radiotherapy (SRT) in the treatment of ONSMs is limited because of the rare incidence of this tumor. We present a series of patients with ONSM who were treated with SRT. METHODS: Five patients (three women, two men), ranging in age from 40 to 73 years, presented with progressive visual loss with decreased visual field, visual acuity, and color vision affecting six eyes (one patient had tumor involving both optic nerves). One patient also presented with proptosis and diplopia. Five eyes had functional residual vision (range, 20/20 to 20/40), and one eye was completely blind. All five patients were diagnosed clinically and radiographically to have an ONSM. Three were intraorbital, one was intracanalicular as well as intraorbital, and one was a left ONSM extending through the optic foramen into the intracranial space and involving the right optic nerve. The five functional eyes were treated with SRT by use of 1.8-Gy fractions to a cumulative dose of 45 to 54 Gy. RESULTS: Follow-up ranged from 1 to 7 years, and serial magnetic resonance imaging revealed no changes in the size of the tumor in all five patients. Four patients experienced dramatic improvement in visual acuity, visual field, and color vision within 3 months after SRT. One patient remained stable without evidence of visual deterioration or disease progression. None had radiation-induced optic neuropathy. CONCLUSION: SRT may be a viable option for treatment of primary ONSM in patients with documented progressive visual deterioration, and it may be effective in improving or stabilizing remaining functional vision.

The sodium ions inside a lipophilic G-quadruplex channel as probed by solid-state (23)Na NMR.

We report solid-state 23Na NMR and X-ray crystallographic results for a self-assembled G-quadruplex channel formed by a guanine nucleoside, 5'-tert-butyl-dimethylsilyl-2',3'-O-isopropylidene guanosine (G 1). The study provides an unambiguous 23Na NMR identification for the Na+ ions inside a lipophilic G-quadruplex channel. The crystalline nature of the sample yields a remarkably high resolution in the 23Na multiple-quantum magic-angle spinning (MQMAS) spectrum, making it possible to extract very accurate 23Na NMR parameters for each of the three crystallographically distinct Na sites. The observation of a single Na+ ion from a 9-kDa system demonstrates the potential of solid-state 23Na NMR as a complementary technique to X-ray for detecting Na+ ions in biological structures.